code: def test_vision_transformer(self):
      config = OmegaConf.structured(AlbefVitEncoder.Config())
      encoder = AlbefVitEncoder(config)
      x = torch.rand((1, 3, 224, 224))
      output = encoder(x)
      self.assertEqual(output.size(-1), config.out_dim)
  
file_path: mmf/tests/models/test_albef.py
imports: import unittest
  import torch
  from mmf.models.albef.vit import AlbefVitEncoder
  from omegaconf import OmegaConf
  from tests.test_utils import setup_proxy
  from torch import nn
label_desc: Use image node_id 3 for calling the TestAlbefEncoders obj's underlying member method code with example usage: obj.test_vision_transformer() without return types